Decide where you're going to build everything. I decided to create a directory called hammer in my home directory.

cd ~
mkdir -p hammer/source
cd hammer/source

Note: If you copy the whole directory tree from the CD, you'll get a directory called SOURCE which will be read-only. I prefer lowercase filenames, so I renamed the files. The files on the CD were also truncated to 8.3 filenames, so the names won't match what you see here.

Grab the latest files (these were from the Hammer_Board_Software page). This assumes that you're still in the source directory

tar xzf Buildroot-01032008.tar.gz
cd buildroot
cp Hammer-config .config
make menuconfig
Exit from menuconfig without making any changes. This creates the .config.cmd file
make
cd ..

Add the cross compiler tools into your path. You may want to add this to your ~/.bashrc, although you should replace $(pwd) with the absolute path to your hammer/source directory.

export PATH=$(pwd)/buildroot/build_arm/staging_dir/bin:${PATH}

Build the kernel:

tar xzf linux-2.6.22.tar.gz
gunzip -c Hammer-linux-2.6.22-09122007.diff.gz | patch -p0
cd linux-2.6.22
edit the Makefile and add the following 2 lines to the top of the Makefile
ARCH=arm
CROSS_COMPILE=arm-linux-
make oldconfig
make zImage